Military weapons systems are inherently dangerous for a variety of reasons. Military personnel or operators who operate short-range and long-range weapons who are required to be physically located at the weapons are exposed to snipers, shrapnel, roadside bombs, and other enemy weapons. Even if the weapons systems are carried on a military personnel carrier, (e.g., tank or Humvee), if the operator is required to be outside the confines of the military personnel carrier, then there is a higher risk of injury or death than if the operator were able to operate the weapons system or sensing system (e.g., electro-optical system) remotely from inside the personnel carrier.
As military weapons have improved over the years, one form of improvement has been to remotely control sensing systems (e.g., imaging, laser, and other electro-optical sensing systems) of weapons systems. While remotely controlling sensing systems of weapons systems is advantageous from a safety perspective, control and accuracy of the sensing systems have suffered for a variety of reasons. First, weapons systems must perform under rigorous conditions, such as on moving vehicles. Second, situational performance of weapons systems must comply with rigorous operational specifications, such as being able to track long-range targets moving at relatively slow speeds. In tracking long-range targets, the sensing systems are required to provide very accurate pointing and low-rate tracking, such as 0.005 degrees per second for a certain period of time (e.g., 30 seconds), yet also provide for high rate slewing (e.g., 60 degrees per second) to enable an operator to react to targets at different locations and ranges from the weapons systems. Third, a hand controller has to provide an operator with easy, intuitive control and “feel” to minimize training time and effectiveness during combat situations.
Hand controllers for controlling sensing systems of weapons systems that operate under the operational parameters described above have traditionally produced non-linear outputs, which makes the job of operators difficult as these non-linear controllers produce “unpredictable” and non-intuitive results. For example, a hand controller that produces a 10 degree per second slew rate output for one foot-pound of torque operator input (i.e., 10:1 slew rate) and a 40 degree per second slew rate output for two foot-pounds of torque operator input (i.e., 20:1 slew rate) is difficult to control even for experienced operators due to producing a non-linear slew rate output. Ultimately, controllability of a sensing system of a weapons system is a function of operator “feel” in using a hand controller.